Footwear and a method for making the same

ABSTRACT

A method for making a footwear includes the steps of disposing a pad between an upper and an outsole, placing an assembly of the pad, the upper, and the outsole in a mold in such a manner that the assembly forms first, second and third gaps thereamong, and filling and molding a molding material in the first, second and third gaps in the mold to form a midsole bonded to the pad, the upper, and the outsole.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the invention

[0002] This invention relates to a footwear and a method for making the same, more particularly to a footwear with a pad between an upper and an outsole thereof and to a method for making the same.

[0003] 2. Description of the related art

[0004]FIG. 1 illustrates a conventional method for forming a midsole 102 between an upper 2 and an outsole 1 of a footwear in a mold 4. Formation of the footwear is performed on a rotary type injection molding machine (not shown) which includes an injection device and a rotatable disc with a plurality of identical molds thereon for mass production. In operation, the disc continuously rotates in such a manner that each mold is injected with a molding material via the injection device when the mold is turned to an injecting position of the injection device, and is continuously turned along with the disc to permit the injected molding material to undergo curing and cooling processes. The thus formed footwear is then removed from the mold when the latter runs through a cycle.

[0005] The aforesaid method is disadvantageous in that when a foamable material is used as the molding material, the curing time is longer as the dimension of the midsole 5 is larger, which increases the aforesaid cycle of the mold on the machine and slows down the production rate of the footwear. Since the machine is relatively expansive, higher costs are incurred when the production rate is low. Furthermore, the midsole 5 is required to have a high density and a closed cell structure for preventing penetration of water from an outer surface of the exposed portion of the midsole 5.

SUMMARY OF THE INVENTION

[0006] Therefore, the object of the present invention is to provide a method for making a footwear that is capable of overcoming the aforementioned drawbacks.

[0007] Another object of this invention is to provide a footwear prepared by the method of this invention and including a pad that can be made from a mixture containing plastic waste and that is positioned between an upper and an outsole of the footwear by a positioning unit.

[0008] According to one aspect of the present invention, a method for making a footwear comprises the steps of: preparing an upper that has a bottom surface, an outsole that has a bottom wall with front and rear ends, and a peripheral side wall which extends from a periphery of the bottom wall, and a pad that has top and bottom faces, and a peripheral side face interconnecting the top and bottom faces; mounting the upper on a last; placing the outsole, the pad, and an assembly of the upper and the last in a mold in such a manner that the pad is disposed between the outsole and the upper, that the pad extends between the front and rear ends of the bottom wall of the outsole, that the top face of the pad confronts and is spaced apart from the bottom surface of the upper to form a first gap therebetween, that the bottom face of the pad confronts and is spaced apart from the bottom wall of the outsole to form a second gap therebetween, and that the peripheral side face of the pad confronts and is spaced apart from the peripheral side wall of the outsole to form a third gap which is in fluid communication with the first and second gaps; and filling and molding a molding material in the first, second, and third gaps in the mold so as to form a midsole that is bonded to the bottom surface of the upper, the bottom wall and the peripheral side wall of the outsole, and the top face, the bottom face, and the peripheral side face of the pad.

[0009] According to another aspect of the present invention, a footwear comprises: an upper having a bottom surface; an outsole vertically spaced apart from the bottom surface of the upper, and having a bottom wall and a peripheral side wall that extends from a periphery of the bottom wall toward the upper, the bottom wall having opposite front and rear ends; a pad extending between the front and rear ends of the bottom wall of the outsole and disposed between the upper and the outsole, the pad having a top face that confronts and that is spaced apart from the bottom surface of the upper to form a first gap therebetween, a bottom face that confronts and that is spaced apart from the bottom wall of the outsole to form a second gap therebetween, and a peripheral side face that confronts and that is spaced apart from the peripheral side wall of the outsole to form a third gap which is in fluid communication with the first and second gaps; and a midsole which is a separate piece from the pad, which is made from a molding material that fills the first, second, and third gaps, and which is bonded to the bottom surface of the upper, the bottom wall and the peripheral side wall of the outsole, and the top face, the bottom face, and the peripheral side face of the pad.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In the drawings which illustrate embodiments of the invention,

[0011]FIG. 1 is a cross-sectional side view to illustrate a conventional method for making a footwear;

[0012]FIG. 2 is a block diagram illustrating consecutive steps of a method embodying this invention for making a footwear;

[0013]FIG. 3 is a sectional side view to illustrate how a midsole is formed in an assembly of an outsole, an upper, and a pad of the footwear according to the method of this invention;

[0014]FIG. 4 is a sectional rear view to illustrate how the midsole is formed in the assembly of the outsole, the upper, and the pad according to the method of this invention;

[0015]FIG. 5 is an exploded perspective view illustrating configurations of the pad and the outsole of the footwear of FIG. 3;

[0016]FIG. 6 is a sectional top view of the footwear of FIG. 3 that embodies this invention;

[0017]FIG. 7 is a sectional top view of a second preferred embodiment of another footwear of this invention that is modified from that shown in FIG. 6; and

[0018]FIG. 8 is a sectional side view of a second embodiment of another method of this invention that uses a mold modified from that shown in FIG. 3.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019]FIG. 2 shows consecutive steps of a method embodying this invention for making a footwear by using the aforesaid rotary type injection molding machine (not shown).

[0020] With reference to FIGS. 3 to 6, the method includes the steps of: preparing an upper 30 that has a bottom surface 31, an outsole 10 that has a bottom wall 11 with opposite front and rear ends 17, 18, and a peripheral side wall 13 which extends from a periphery of the bottom wall 11 in a transverse direction relative to the bottom wall 11, and a pad 20 that has top and bottom faces 21, 22, and a peripheral side face 23 interconnecting the top and bottom faces 21, 22; mounting the upper 30 on a last 300; placing the outsole 10, the pad 20, and an assembly of the last 300 and the upper 30 in a mold 200 in such a manner that the pad 20 is disposed between the outsole 10 and the upper 30, that the pad 20 extends between the front and rear ends 17, 18 of the bottom wall 11 of the outsole 10, that the top face 21 of the pad 20 confronts and is spaced apart from the bottom surface 31 of the upper 30 to form a first gap 51 therebetween, that the bottom face 22 of the pad 20 confronts and is spaced apart from the bottom wall 11 of the outsole 10 to form a second gap 52 therebetween, and that the peripheral side face 23 of the pad 20 confronts and is spaced apart from the peripheral side wall 13 of the outsole 10 to form a third gap 53 which is in fluid communication with the first and second gaps 51, 52 (see FIG. 4); and filling and molding a molding material in the first, second, and third gaps 51, 52, 53 in the mold 200 so as to form a midsole 40 that is bonded to the bottom surface 31 of the upper 30, the bottom wall and the peripheral side wall 11, 13 of the outsole 10, and the top face 21, the bottom face 22, and the peripheral side face 23 of the pad 20.

[0021] A positioning unit includes a plurality of spaced apart positioning posts 15 that are integrally formed with the outsole 10 and that project from the bottom wall 11 of the outsole 10 toward the pad 20. The pad 20 is formed with a plurality of positioning holes 25, each of which is confined by a hole-confining wall 251. The positioning posts 15 extend into the positioning holes 25, and are in frictional contact with the hole-confining walls 251 of the positioning holes 25 (see FIG. 4), respectively, so as to position the pad 20 between the upper 30 and the outsole 10.

[0022] The positioning unit further includes a plurality of supporting seats 14, each of which is integrally formed with and each of which projects from the bottom wall 11 of the outsole 10 toward the pad 20 and each of which has a top face 141 in contact with the bottom face 22 of the pad 20 so as to enhance positioning of the pad 20 between the upper 30 and the outsole 10.

[0023] The pad 20 is further formed with a plurality of apertures 24 that are in fluid communication with the first and second gaps 51, 52. The midsole 40 fills the apertures 24 so as to enhance the bonding between the midsole 40 and the pad 20.

[0024] The pad 20 can be made from a mixture of ethylene vinylacetate copolymer and plastic waste. The molding material can be made from a mixture of polyols and isocynate or from polyvinyl chloride.

[0025] Referring to FIGS. 3 and 5, the peripheral side wall 13 of the outsole 10 is formed with an anchored flange 131 for anchoring on a periphery of the mold 200.

[0026]FIG. 7 shows a second preferred embodiment of another footwear of this invention that is modified from that shown in FIG. 6 and that includes a plurality of spaced apart positioning studs 251 projecting from the peripheral side face 23 of the pad 20 to abut against the peripheral side wall 13 of the outsole 10 so as to prevent lateral movement of the pad 20 during the molding process.

[0027]FIG. 8 shows a second embodiment of another method of this invention which uses a mold 200′ modified from that shown in FIG. 3. The mold 200′ is formed with a plurality of protrusions 230 in place of the aforesaid positioning posts 15 and that extend through the bottom wall 11 of the outsole 10 and into the positioning holes 25, respectively. A plurality of second protrusions 220 project from the mold 200 into the bottom wall 11 of the outsole 10 for positioning the outsole 10.

[0028] With the inclusion of the pad 20 in the method of this invention, the drawbacks as encountered in the prior art can be eliminated. Moreover, since the pad 20 can be made from plastic waste, the manufacturing cost attributed to the midsole 40 can be reduced.

[0029] With the invention thus explained, it is apparent that various modifications and variations can be made without departing from the spirit of the present invention. It is therefore intended that the invention be limited only as recited in the appended claims. 

I claim:
 1. A method for making a footwear, comprising the steps of: preparing an upper that has a bottom surface, an outsole that has a bottom wall with front and rear ends, and a peripheral side wall which extends from a periphery of said bottom wall, and a pad that has top and bottom faces, and a peripheral side face interconnecting said top and bottom faces; mounting said upper on a last; placing said outsole, said pad, and an assembly of said upper and said last in a mold in such a manner that said pad is disposed between said outsole and said upper, that said pad extends between said front and rear ends of said bottom wall of said outsole, that said top face of said pad confronts and is spaced apart from said bottom surface of said upper to form a first gap therebetween, that said bottom face of said pad confronts and is spaced apart from said bottom wall of said outsole to form a second gap therebetween, and that said peripheral side face of said pad confronts and is spaced apart from said peripheral side wall of said outsole to form a third gap which is in fluid communication with said first and second gaps; and filling and molding a molding material in said first, second, and third gaps in said mold so as to form a midsole that is bonded to said bottom surface of said upper, said bottom wall and said peripheral side wall of said outsole, and said top face, said bottom face, and said peripheral side face of said pad.
 2. The method of claim 1, wherein said pad is disposed between said upper and said outsole via a positioning unit that includes a plurality of spaced apart positioning posts which are integrally formed with said outsole and which project from said bottom wall of said outsole toward said pad, said pad being formed with a plurality of positioning holes, each of which is confined by a hole-confining wall, said positioning posts extending into said positioning holes and being in frictional contact with said hole-confining walls of said positioning holes, respectively, so as to position said pad between said upper and said outsole.
 3. The method of claim 2, wherein said positioning unit further includes a plurality of supporting seats, each of which is integrally formed with and each of which projects from said bottom wall of said outsole toward said pad and each of which has a top face in contact with said bottom face of said pad so as to enhance positioning of said pad between said upper and said outsole.
 4. The method of claim 1, wherein said pad is made from a mixture of ethylene vinylacetate copolymer and plastic waste, said molding material being made from a mixture of polyols and isocynate.
 5. A footwear comprising: an upper having a bottom surface; an outsole vertically spaced apart from said bottom surface of said upper, and having a bottom wall and a peripheral side wall that extends from a periphery of said bottom wall toward said upper, said bottom wall having opposite front and rear ends; a pad extending between said front and rear ends of said bottom wall of said outsole and disposed between said upper and said outsole, said pad having a top face that confronts and that is spaced apart from said bottom surface of said upper to form a first gap therebetween, a bottom face that confronts and that is spaced apart from said bottom wall of said outsole to form a second gap therebetween, and a peripheral side face that confronts and that is spaced apart from said peripheral side wall of said outsole to form a third gap which is in fluid communication with said first and second gaps; and a midsole which is a separate piece from said pad, which is made from a molding material that fills said first, second, and third gaps, and which is bonded to said bottom surface of said upper, said bottom wall and said peripheral side wall of said outsole, and said top face, said bottom face, and said peripheral side face of said pad.
 6. The footwear of claim 5, further comprising a positioning unit for interconnecting said pad and said outsole so as to position said pad between said upper and said outsole, said positioning unit including a plurality of spaced apart positioning posts that are integrally formed with said outsole and that project from said bottom wall of said outsole toward said pad, said pad being formed with a plurality of positioning holes, each of which is confined by a hole-confining wall, said positioning posts extending into said positioning holes and being in frictional contact with said hole-confining walls of said positioning holes, respectively, so as to position said pad between said upper and said outsole.
 7. The footwear of claim 6, wherein said positioning unit further includes a plurality of supporting seats, each of which is integrally formed with and each of which projects from said bottom wall of said outsole toward said pad and each of which has a top face in contact with said bottom face of said pad so as to enhance positioning of said pad between said upper and said outsole.
 8. The footwear of claim 7, wherein said pad is further formed with a plurality of apertures that are in fluid communication with said first and second gaps and that are filled by said midsole.
 9. The footwear of claim 5, wherein said pad is made from a mixture of ethylene vinylacetate copolymer and plastic waste, and said molding material is made from a mixture of polyols and isocynate. 